Close to Death

That swivel design (the old Petzl swivel) is designed for hard attachment not on cord. The shoulders are rounded but a ring (like the one on the BII) or the newer Petzl swivel design has a bigger radius.

Why use narrow diameter cord for a bridge? I don't care how strong it is.

Good question though, what kind of cord is that? Never heard of "techno".

How long were you climbing on it before it failed?

Glad it all worked it out ok.
-moss
 
[ QUOTE ]
What is 'techno' cord? From the pics the bridge looked very worn.

[/ QUOTE ]

It looks like a technora 5/16" 16 strand hollow braid. Israel is bringing the cord to me to look at today. I'll do my best to identify it and post what I find.
I agree that there is excessive wear.
 
[ QUOTE ]
[ QUOTE ]
What is 'techno' cord? From the pics the bridge looked very worn.

[/ QUOTE ]

It looks like a technora 5/16" 16 strand hollow braid. Israel is bringing the cord to me to look at today. I'll do my best to identify it and post what I find.
I agree that there is excessive wear.

[/ QUOTE ]

Yep, looks like the coated red technora from Atlantic Braids. The bridge looks severely abraded.

Kinda like what Moss said, it's a bridge, it needs to be super strong, absolutely trustworthy. If it fails...
 
I'm kind of at a loss for trying to gain a sense of why that type of failure would occur from just being a bridge.

The frayed ends, zoomed-in on, don't look like they had been abraded but instead look like massive and rapid load tears, can't imagine the weight applied, even shocked if it's only a climber.

Almost like something corrosive ate away without noticable evidence of tampering or something?
 
I thought 16 strand technora too. Maybe that's why he's calling it techno chord. The bridge was hand spliced right? How was it spliced? Did you use any foreign objects in the splice? I'm talking about lubricants or stuff like that?
 
[ QUOTE ]
I am know freaked out about bridges. What should I use. I spliced my own bridge and it was techno cord.

[/ QUOTE ]

What exact cord was this? How old? You never fell on it? I'd say mail it to the manufacturer along with a note and the photos of the swivel and see what they say.
 
Splicing failures are pretty evident...that's load trauma there, almost like an old crusty Arbo-plex was used to tow an old Chevy back to the shop, thru rush-hour traffic and over the great divide.
 
[ QUOTE ]
...almost like an old crusty Arbo-plex was used to tow an old Chevy back to the shop, thru rush-hour traffic and over the great divide.

[/ QUOTE ]

That's it! I think you nailed it.
-moss
 
Was this new line when it was made into the bridge, or was it from a section of rope that "looked" good when you put it on your saddle? Just wondering if there was a shock load that maybe occured before the rope was put on the saddle.
 
I have the suspect bridge in hand. It is a 16 strand technora 5/16's diameter hollow braid from Atlantic Braids. It's overall length is 12", and was spliced onto the rings of a "Glide" harness as a new and unused product, replacing the original bridge. It appears the fibers were indeed cut, due to the looks of the individual strands and fibers. In my opinion, the product was not at all defective. I was able to check the Petzl swivel as well. There are sharp edges on the old gold and black models, but the new (all black) model has the sharp edges rounded. I told IG not to use the swivel anymore and use a bridge that has a protective cover.
I will examine the bridge more thoroughly tonite and take some pics as well. Til then.......
 
Israel,

Glad to hear you're OK after this accident. If anyone can figure out what happened to that cord it would be Norm..

At first glance I figured on the cord being cut, but how the swivel could have done the cutting I have no idea.

Do you routinely take pictures of your worn gear as part of your regular inspection, or was it just luck to have such a perfect before and after? I only ask because it seems that digital photos could be a great way to keep an eye on wear over a long period of time.
 
Holy macarole, what a scary accident. So glad you are ok.

I do feel this bridge failure was foreseeable. Technora is in the family of aramid fibers that are designated as "mildly self-abrasive". Combine that with a relatively sharp-edged item in the form of the old style swivel, plus the increased load factor that a bridge sees due to the angles of the load, at angles greater than 120 deg having additional multipliers, 150 deg has 200%. That is a lot of stress to be putting on a fiber that was not designed for this purpose.

Kind of a heads up for everyone experimenting with some of these super strong new fibers whose primary attributes are for uses in different circumstances.

I, also, will be very interested in Norm's findings.

Dave
 
[ QUOTE ]
...I do feel this bridge failure was foreseeable. Technora is in the family of aramid fibers that are designated as "mildly self-abrasive". Combine that with a relatively sharp-edged item in the form of the old style swivel, plus the increased load factor that a bridge sees due to the angles of the load, at angles greater than 120 deg having additional multipliers, 150 deg has 200%. That is a lot of stress to be putting on a fiber that was not designed for this purpose.

[/ QUOTE ]

Spot-on.
-moss
 
I dont buy it. Theres more to the story than whats been told. I seriously doubt a bridge would just fail like that, and if it did, its obvious the user didnt ever bother to inspect the bridge or it would have been removed from service long ago.
 
I've used that swivel on a rope bridge (fly) and noticed extremely fast, excessive wear on the bridge. Switching to a ring or krab attachment made all the difference. Get rid of the old swivel, IMO.

Chris
 
I agree, something else had to contribute to the failure. I used that cordage for a split tail for a while, then left it outside for over a year on a tieout for my dog. It still looks fine. Well, fine-ish.

Good thing we've got our top man on it. Dr. Hall, forensic ropeologist.
 
[ QUOTE ]

Good thing we've got our top man on it. Dr. Hall, forensic ropeologist.

[/ QUOTE ]

Definetly!
 
First of all, I'm glad you are ok. I was originally going to call shenanegans on this and call it a made up story to ruffle feathers. But seeing as how IG took the time to bring Norm the bridge changed my mind. How was the saddle stored? Ive seen saddles lumped in with chainsaws, handsaws, and many things that can nick, or damage a rope. The bridge looks like it busted at the midpoint which is where the swivel would be when weighted. So unless the bridge was cut with a handsaw with weight on the climbing line, id have to say the swivel did it.

I have a pair of hand ascenders that when i first tried, had positioned under a prussic with a micro pulley. on srt, the ascenders would contact the bottom of the micro pulley and push the prussic up. I abandoned this method after a few tries because the metal to metal contact was ruining the ascenders. It caused burs and divets to the soft aluminum alloys of the ascenders after literily 5 times. I wonder if the swivel contacting the bridges rings, or the carabiners slapping the swivel caused small burs that could have abraided the bridge over time.
 
I don't think the 'before' pic looks like the same bridge. It appears more worn than the broken bridge.

It's very strange that the broken bridge really doesn't appear overly worn on either side of the break. I'm wondering if the cord was damaged during the initial splcing or even spliced horribly wrong (i hope not.)
 
You must log in or register to reply here.

New threads New posts

Back
Top Bottom